@Grippo1,
Welcome to HP Forums, this is a great place to get support, find answers and tips.
Thank you for posting your query, I'll be more than glad to help you out.
I understand that your HP ENVY 120 e-All-in-One Printer ejects blank sheets from the rear while printing.
Don't worry as I have a few steps that should help fix this issue.
This issue could occur if there is a rear access door for the printer and is not closed.
If it is closed, then you may follow the steps provided in the link: Troubleshooting Print Quality Issues
Also, you may check the link: http://hp.care/2k5oSZQ
Let me know how that works.
I hope you have a good day ahead.
Rainbow23
I am an HP Employee
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